This is the first of three chapters about HTTP. In this chapter, you will learn how to use the protocol from the point of view of a client program that wants to fetch and cache documents and perhaps submit queries or data to the server as well. In the process, you will learn the rules of how the protocol operates. Chapter 10 will then look at the design and deployment of HTTP servers. Both chapters will consider the protocol in its most pristine conceptual form, that is, simply as a mechanism for fetching or posting documents.